X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fbitcount.h;fp=src%2Fbitcount.h;h=0000000000000000000000000000000000000000;hp=7609da40c30c2282ecc3dab112a70b7185bbef1d;hb=8fb45caadef67fb2ccc27857c15ade987d9f5e2f;hpb=900279a06f432fbba63b5a320028830b40e06e3e diff --git a/src/bitcount.h b/src/bitcount.h deleted file mode 100644 index 7609da40..00000000 --- a/src/bitcount.h +++ /dev/null @@ -1,105 +0,0 @@ -/* - Stockfish, a UCI chess playing engine derived from Glaurung 2.1 - Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad - Copyright (C) 2015-2016 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad - - Stockfish is free software: you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation, either version 3 of the License, or - (at your option) any later version. - - Stockfish is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. - - You should have received a copy of the GNU General Public License - along with this program. If not, see . -*/ - -#ifndef BITCOUNT_H_INCLUDED -#define BITCOUNT_H_INCLUDED - -#include - -#include "types.h" - -enum BitCountType { - CNT_64, - CNT_64_MAX15, - CNT_32, - CNT_32_MAX15, - CNT_HW_POPCNT -}; - -/// Determine at compile time the best popcount<> specialization according to -/// whether the platform is 32 or 64 bit, the maximum number of non-zero -/// bits to count and if the hardware popcnt instruction is available. -const BitCountType Full = HasPopCnt ? CNT_HW_POPCNT : Is64Bit ? CNT_64 : CNT_32; -const BitCountType Max15 = HasPopCnt ? CNT_HW_POPCNT : Is64Bit ? CNT_64_MAX15 : CNT_32_MAX15; - - -/// popcount() counts the number of non-zero bits in a bitboard -template inline int popcount(Bitboard); - -template<> -inline int popcount(Bitboard b) { - b -= (b >> 1) & 0x5555555555555555ULL; - b = ((b >> 2) & 0x3333333333333333ULL) + (b & 0x3333333333333333ULL); - b = ((b >> 4) + b) & 0x0F0F0F0F0F0F0F0FULL; - return (b * 0x0101010101010101ULL) >> 56; -} - -template<> -inline int popcount(Bitboard b) { - b -= (b >> 1) & 0x5555555555555555ULL; - b = ((b >> 2) & 0x3333333333333333ULL) + (b & 0x3333333333333333ULL); - return (b * 0x1111111111111111ULL) >> 60; -} - -template<> -inline int popcount(Bitboard b) { - unsigned w = unsigned(b >> 32), v = unsigned(b); - v -= (v >> 1) & 0x55555555; // 0-2 in 2 bits - w -= (w >> 1) & 0x55555555; - v = ((v >> 2) & 0x33333333) + (v & 0x33333333); // 0-4 in 4 bits - w = ((w >> 2) & 0x33333333) + (w & 0x33333333); - v = ((v >> 4) + v + (w >> 4) + w) & 0x0F0F0F0F; - return (v * 0x01010101) >> 24; -} - -template<> -inline int popcount(Bitboard b) { - unsigned w = unsigned(b >> 32), v = unsigned(b); - v -= (v >> 1) & 0x55555555; // 0-2 in 2 bits - w -= (w >> 1) & 0x55555555; - v = ((v >> 2) & 0x33333333) + (v & 0x33333333); // 0-4 in 4 bits - w = ((w >> 2) & 0x33333333) + (w & 0x33333333); - return ((v + w) * 0x11111111) >> 28; -} - -template<> -inline int popcount(Bitboard b) { - -#ifndef USE_POPCNT - - assert(false); - return b != 0; // Avoid 'b not used' warning - -#elif defined(_MSC_VER) && defined(__INTEL_COMPILER) - - return _mm_popcnt_u64(b); - -#elif defined(_MSC_VER) - - return (int)__popcnt64(b); - -#else // Assumed gcc or compatible compiler - - return __builtin_popcountll(b); - -#endif -} - -#endif // #ifndef BITCOUNT_H_INCLUDED